Information Processing Apparatus, Control Method Therefor and Storage Medium

1. An information processing apparatus comprising: a mirroring unit that performs mirroring for synchronizing storage contents of a first storage unit and a second storage unit; a control unit that displays on a display unit, if one storage unit, among the first storage unit and the second storage unit, for which the mirroring is performed, is not attached, a screen for accepting an instruction that the apparatus is activated using information stored in another storage unit attached when accepting the instruction; a registration unit that (i) does not register the one storage unit as a failed storage unit before accepting the instruction via the screen, and (ii) registers the one storage unit as the failed storage unit after accepting the instruction via the screen, an acquisition unit that acquires an identifier from each of the first storage unit and the second storage unit when an activation of the apparatus has been instructed; and a comparison unit that compares an identifier acquired by said acquisition unit with an identifier held in advance in said apparatus, wherein said control unit displays on the display unit, if a comparison result of said comparison unit indicates that there is one matching identifier, the screen for accepting the instruction that the apparatus is activated using the information stored in the other storage unit which the matching identifier is matched, wherein a processor is included in the apparatus.

2. The apparatus according to claim 1 , wherein the screen includes a forced activation button for accepting the instruction that the apparatus is activated using information stored in the other storage unit, and wherein the control unit activates, when a user selects the forced activation button, the apparatus using the information stored in the other storage unit.

3. A control method for an information processing apparatus, the method comprising: a performing step of performing mirroring for synchronizing storage contents of a first storage unit and a second storage unit; a displaying step of displaying on a display unit, by a control unit, if one storage unit, among the first storage unit and the second storage unit, for which the mirroring is performed, is not attached, a screen for accepting an instruction that the apparatus is activated using information stored in another storage unit attached when accepting the instruction; a registering step of (i) not registering the one storage unit as a failed storage unit before accepting the instruction via the screen, and (ii) registering the one storage unit as the failed storage unit after accepting the instruction via the screen; an acquisition step of acquiring an identifier from each of the first storage unit and the second storage unit when an activation of the apparatus has been instructed; a comparison step of comparing an identifier acquired by said acquisition unit with an identifier held in advance in said apparatus; and a second displaying step of displaying on the display unit, if a comparison result of said comparison unit indicates that there is one matching identifier, a screen for accepting an instruction that the apparatus is activated using information stored in the other storage unit which the matching identifier is matched.

4. A non-transitory computer-readable storage medium storing a computer program for causing a computer to execute each step of a control method for an information processing apparatus according to claim 3 .